A noticeable trend at the recent Hannover Fair was the emergence of “intelligent” versions of previously “dumb” mechanical devices. Several exhibitors announced “smart” versions of traditional mechanical components, designed to connect to the Internet of Things and to Industry 4.0 applications.

For example, the belt-maker Continental was demonstrating “smart” power transmission belts and air springs. It sees this as a key growth area where it can add value for its customers. “Digitalisation is a major opportunity for us,” declared Hans-Jürgen Duensing, Continental’s board member responsible for its ContiTech division. “We’re working tirelessly to make our products and systems smarter.” He believes that predictive maintenance will be “a key driver of growth and efficiency in many of the industries in which we operate”.

One innovation on the ContiTech stand was a prototype of an intelligent belt that continuously measures parameters such as temperature, elongation, surface wear, and corrosion of its steel cords, allowing users to replace belts before they fail. Internal and external sensors will send data on the condition of the belt to controls or PCs, using technologies such as wireless RFID.

ContiTech was also demonstrating a range of air springs whose internal pressure and height are measured ultrasonically to a resolution of ±1mm in over a range of up to 500mm. If application conditions change – due, for example, to load changes or uneven surfaces – the system can compensate automatically. “We are setting a milestone in the field of air spring technology,” says Verena Weiss, head of ContiTech’s air spring systems business, “particularly due to the fact that the digital air springs do not require mechanical control components”.

The gripper manufacturer, Schunk, was demonstrating a “smart” parallel gripper which has on-board sensors and the processing power to capture data about items it is holding – such as their size and elasticity – and to use this to identify the items, detect any damage, and decide whether a component is good or bad. The results, as well as the measured data, can be transferred to control systems via Profinet. The EGL Profinet gripper has a variable stroke and a gripping force of 50–600N.

Schunk was also demonstrating how it can send data from its grippers to analysis tools running in the cloud, allowing users to monitor their equipment in real time on devices such as smartphones.

A prototype linear guide with embedded Sensosurf sensors

The Taiwanese motion control manufacturer, HiWin Technologies, unveiled an “intelligent” ballscrew with built-in sensors to monitor preload status, lubrication, vibration levels and temperature. The data can be used to prevent unexpected machine shutdowns and to improve productivity. HiWin says that the lubrication monitoring function can cut lubricant consumption by up to 70%.

A German start-up called Sensosurf has developed a technology for creating sensors that are less than 5µm thick – ten times thinner than a human hair – and can be embedded into the surfaces of components such as bearings, gears and linear guides. They are covered by a protective layer of glass or carbon-fibre-reinforced plastics of a similar thickness. At Hannover, Sensorsurf was demonstrating its technology in use in what it describes as the world’s first intelligent flange and pedestal bearings.

The sensors work on a variety of measurement principles, including resistive, capacitive, thermoelectric and inductive. The resistive versions can measure temperatures and strain levels down to 0.01µm/m, while the thermoelectric versions can sense temperature changes with a resolution of less than 1K.

Sensosurf says that its sensors can generate data that was not previously available and use it for applications such as predictive maintenance. The sensors can withstand more than 2.5 million cycles of aluminium or steel particles scratching across their surfaces. They can also operate in temperatures up to 250°C – or 500°C in special applications.